The Supreme Court sentenced a conscientious objector to 18 months in prison, officials said Wednesday, upholding past court judgments rejecting religious faith as a justifiable exemption to military duty.

The defendant, surnamed Lee, had refused to serve on religious grounds. He violated conscription laws according to the judges.

Lee is a Jehovah’s Witness, many of whom have been sent to prison for refusing to enter the military. Jehovah’s Witnesses say the Bible preaches pacifism.

All South Korean men are obligated to serve in the military, unless the Military Manpower Administration deems a draftee is physically or psychologically unfit.

Although South Korea offers religious recruits noncombat duty options such as clerical assistantships and positions as military chaplains, all draftees must undergo basic training ― during which trainees are taught to shoot firearms and throw grenades.

Jehovah’s Witnesses cite basic training as a reason for declining to serve.

Wednesday’s ruling also rejected last year’s United Nations High Commissioner for Human Rights report that advised South Korea to provide conscientious objectors with civil service options other than the military.

“(The report) does not have binding powers,” a justice said.

The Supreme Court in 2004 said declining service on religious grounds went against the Military Service Act. The Constitutional Court, a legal body judging the constitutionality of laws, said in the same year that not acknowledging pacifist objectors was constitutional.

Opponents of conscientious objection also cite national security and the fear that other draft dodgers could abuse the system.

South Korea is still technically at war with North Korea after an armistice, and not a peace treaty, ended the Korean War in 1953. North Korea has launched various attacks on South Korea since then. In 2010, North Korea sunk a South Korean corvette in the West Sea, killing 46, and shelled a South Korean island near the inter-Korean border later that year.

Officials also say it would be difficult to differentiate between those genuinely objecting out of conscience, and those faking religious convictions as an excuse to skip service.